The CIA has opened the year with a flurry of drone strikes in Pakistan, pounding Taliban targets along the country’s tribal belt at a time when the Obama administration is preparing to disclose its plans for pulling most U.S. forces out of neighboring Afghanistan.

A strike Thursday in North Waziristan was the seventh in 10 days, marking a major escalation in the pace of attacks. Drone attacks had slipped in frequency to fewer than one per week last year.

Current and former U.S. intelligence officials attributed the increased tempo to a sense of urgency surrounding expectations that President Obama will soon order a drawdown that could leave Afghanistan with fewer than 6,000 U.S. troops after 2014. The strikes are seen as a way to weaken adversaries of the Afghan government before the withdrawal and serve notice that the United States will still be able to launch attacks.

The rapid series of CIA strikes “may be a signal to groups that include not just al-Qaeda that the U.S. will still present a threat” after most American forces have gone, said Seth Jones, a counterterrorism expert at the Rand Corp. “With the drawdown in U.S. forces, the drone may be, over time, the most important weapon against militant groups.”

U.S. officials also tied the increase to recent intelligence gains on groups blamed for lethal attacks on U.S. and coalition forces in Afghanistan. Among those killed in the drone strikes, according to U.S. officials, was Maulvi Nazir, a Taliban commander accused of planning cross-border raids and providing protection for al-Qaeda fighters.

The CIA may see a diminishing window for using drones with such devastating effectiveness as the military begins sharp reductions in the 66,000 U.S. troops in Afghanistan, current and former officials said.

A former U.S. intelligence official with extensive experience in Afghanistan said the CIA has begun discussing plans to pare back its network of bases across the country to five from 15 or more because of the difficulty of providing security for its outposts after most U.S. forces have left.

The CIA declined to comment.

“As the military pulls back, the agency has to pull back,” the former U.S. intelligence official said on the condition of anonymity, particularly from high-risk outposts along the country’s eastern border that have served as bases for running informant networks and gathering intelligence on al-Qaeda and Taliban strongholds in Pakistan.

Such a retrenchment could slow the process of identifying fresh targets for drone strikes, although the agency is expected to continue operating the remotely piloted planes from fortified bases, such as a landing strip in Jalalabad.

“Essentially we will become Fort Apache in Kabul and the major cities,” the former U.S. intelligence official said, describing a pared back CIA presence. Even if the drones continue to take off and land, the diminished presence in Khost and other locations could hamper “our ability to gather intelligence on where Zawahiri is and what al-Qaeda is doing in the North-West Frontier Province” of Pakistan, he said, referring to al-Qaeda leader Ayman al-Zawahiri and the region now known as Khyber Pakhtunkhwa province.

The CIA’s base plans are among a wide range of issues that the U.S. government has been negotiating with Afghan President Hamid Karzai, who is visiting top officials in Washington this week. A CIA spokesman declined to say whether agency officials had met with Karzai.

The Pakistani government has not publicly protested the stepped-up drone strikes, but reports suggest that they have caused higher-than-usual civilian casualties. Bill Roggio, who tracks drone activity in Pakistan for the Long War Journal Web site, said preliminary information indicates that as many as 11 civilians, along with 30 militants, have been killed so far this year. If true, that civilian count would exceed the total for all of 2012, Roggio said.

U.S. officials disputed that count but declined to provide an alternative figure. U.S. officials have frequently touted the accuracy of the program and claimed that reports exaggerate civilian casualties.

Assessing the civilian toll has been notoriously difficult, partly because the strikes take place in areas almost inaccessible to journalists and independent monitors. The New America Foundation has estimated that the civilian casualty rate was 10 percent in 2012, down from 60 percent in 2006.

The surge in drone activity comes as key leadership positions at the CIA and in Obama’s national security cabinet are in flux.

Former CIA director David H. Petraeus, who had previously commanded coalition forces in Afghanistan, had sought to place tighter restrictions on the agency’s drone campaign in Pakistan, leading to clashes with the head of the CIA’s counterterrorism center, former officials said.

Petraeus resigned in November after admitting to an extramarital affair, leaving his deputy, acting CIA Director Michael J. Morell, with approval authority on drone strikes in Pakistan.

This week, Obama nominated his counterterrorism adviser, John O. Brennan, as the next CIA director. The direction the drone program might take under Brennan, a 25-year CIA veteran, is unclear. He has expressed misgivings about the CIA’s paramilitary mission and expanded the role of other agencies in targeting decisions. But the number of strikes in Pakistan and Yemen soared during Brennan’s tenure at the White House before tapering off in Pakistan over the past two years.

The strikes so far this year have been scattered across North and South Waziristan, semiautonomous regions targeted in the vast majority of the more than 300 strikes carried out by the CIA in Pakistan since 2004.

Among those killed in the latest strikes was Wali Mohammed, a commander described by Roggio as a director of suicide operations for the Taliban.

Pakistanis in the tribal region said they were baffled by the surge in activity.

“This is beyond our understanding why the drone attacks are increased,” a tribal elder from Miran Shah, the main town in North Waziristan, said during a telephone interview. He spoke on the condition of anonymity, citing concern for his safety.

The latest strikes coincided with a broader outbreak of violence in Pakistan. As many as 115 people were killed Thursday in a series of bombings including two in the southern city of Quetta.

Julie Tate in Washington and Haq Nawaz Khan in Peshawar, Pakistan, contributed to this report.

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